Data hiding through arrangement of objects

• US 7,321,667 B2
• Filed: 05/11/2005
• Issued: 01/22/2008
• Est. Priority Date: 01/18/2002
• Status: Expired due to Term

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Stach, John
• Primary Examiner(s): Johns; Andrew W.
• Application Number:
  US11/127,442
• Publication Number:
  US 20050207615A1
• Time in Patent Office: 986 Days
• Field of Search: 382/100, 382/232, 382/284, 713/176, 380/287, 380/51, 380/54, 380/55, 283/72, 283/85, 283/93, 283/113, 283/901, 345/629, 345/634, 345/635, 345/637, 345/641
• US Class Current: 382/100
• CPC Class Codes: G06T 1/0064 Geometric transfor invariant watermarking, e.g. affine transform invariant
• CPC Class Codes: G06T 2201/0051 Embedding of the watermark in the spatial domain
• CPC Class Codes: H04N 1/32149 Methods relating to embedding, encoding, decoding, detection or retrieval operations
• CPC Class Codes: H04N 1/32154 Transform domain methods H04N1/32309 takes precedence
• CPC Class Codes: H04N 1/32187 with selective or adaptive application of the additional information, e.g. in selected frequency coefficients
• CPC Class Codes: H04N 1/32208 involving changing the magnitude of selected pixels, e.g. overlay of information or super-imposition H04N1/32219, H04N1/32224 take precedence
• CPC Class Codes: H04N 1/32229 with selective or adaptive application of the additional information, e.g. in selected regions of the image H04N1/32213 takes precedence
• CPC Class Codes: H04N 1/32251 in multilevel data, e.g. greyscale or continuous tone data
• CPC Class Codes: H04N 1/32309 in colour image data
• CPC Class Codes: H04N 2201/327 which are undetectable to the naked eye, e.g. embedded codes

Abstract

The present invention provides steganographic embedding techniques. A digital watermark signal is reduced to a set of spatial positions. The set of spatial positions sufficiently conveys the digital watermark signal. Message objects are positioned according to the set of spatial positions. Non-message objects are combined with the message objects to form an image or design. The message objects include distinguishable characteristics, e.g., via color, contrast, gray-scale level or luminance, in comparison to the non-message objects. The digital watermark signal is detected by distinguishing the message objects from the non-message objects (e.g., via color or contrast differences) and analyzing the relative placement of the message objects within the image or design.

Claims

1. A method comprising:

providing a digital watermark signal;

thresholding the digital watermark signal to yield a set of position points; and

arranging message objects in accordance with the position points.

2. The method according to claim 1, wherein the message objects comprise at least one type of object from a group of objects comprising:

color level, gray-scale level, luminance value and contrast, to distinguish the message objects from a background or other objects.

3. The method of claim 1 wherein the message objects comprise at least one type of object from a group of objects comprising:

cuts in a field, flowers, marbles, bottle caps, cups, umbrella, crops, grass, balloons, coins, and pictures in a photo-mosaic.

4. The method of claim 1 wherein the message objects comprise at least one of an image segment or a digital image.

5. The method of claim 1, where the message objects are arranged to form at least part of an image.

6. A document including at least a substrate and a digital watermark signal carried by the substrate, the digital watermark signal comprising a set of relevant points identified through reducing a digital watermark signal to the set of relevant points, the set of relevant points comprising location positions relative to the substrate, wherein objects are arranged on the substrate according to the set of relevant points to convey the digital watermark signal.

7. The document of claim 6 wherein the document comprises an image.

8. The document of claim 6 wherein the document comprises a photo-mosaic.

9. The document of claim 8, wherein the objects comprise photographs.

10. A method comprising:

providing a digital watermark signal;

reducing the digital watermark signal to yield a set of spatial placement positions, the set of spatial placement positions comprising a placement map; and

arranging message objects in accordance with the placement map.

11. The method of claim 10, wherein once arranged, the objects convey the digital watermark signal.

12. The method of claim 11, further comprising arranging non-message objects to form an image or design, the non-message objects differing from the message object in at least one of color, contrast, gray-scale or luminance.

13. A method comprising:

providing a digital watermark signal;

reducing the digital watermark signal to a set of spatial positions relative to a fixed area;

arranging a first set of photographs within the fixed area according to the set of spatial positions;

arranging a second set of photographs within the fixed area to complete a photo-mosaic, wherein the first set of photographs is subtly distinguishable from the second set of photographs.

14. The method of claim 13, wherein the first set of photographs is subtly distinguishable by at least one of color, contrast, gray-level or luminance.

15. The method according to claim 14, wherein the arrangement of the first set of photographs conveys the digital watermark signal.

16. A method comprising:

providing a steganographic signal including a message;

reducing the steganographic signal to yield a reduced steganographic signal, wherein the reduced steganographic signal represents the message; and

arranging objects in accordance with the reduced steganographic signal, wherein the objects, once arranged, steganographically convey the message.

17. The method of claim 16, wherein the objects comprise at least one of color level, gray-scale level, luminance value or contrast, to distinguish the message objects from a background or other objects.

18. The method of claim 16, wherein the objects comprise at least one type of object from a group of objects comprising:

cuts in a field, flowers, marbles, bottle caps, cups, umbrella, crops, grass, balloons, coins, and pictures in a photo-mosaic.

19. The method of claim 16, wherein the objects comprise at least one of an image segment or a digital image.

20. The method of claim 16 wherein a host of the reduced steganographic signal comprises at least one of an image or video.

21. A method comprising:

providing a steganographic signal including a message with original data;

reducing the steganographic signal to yield a reduced steganographic signal, wherein the reduced steganographic signal represents the message, and wherein

said act of reducing does not affect recovery of the original data carried in the message; and

embedding the reduced steganographic signal in imagery or video.

22. The method of claim 21, wherein the embedding comprises arranging objects in the imagery or video, wherein the objects, once arranged, convey the message.

23. A method comprising:

providing a signal conveying plural-bit data;

arranging message objects according to the signal, the message objects—

once arranged—

conveying at least the plural-bit data; and

arranging other objects, the other objects hiding or concealing the arrangement of the message objects or the presence of the plural-bit data.